1. Field of the Invention
The present invention relates generally to tracking systems and, more specifically, to a global positioning tracking system for locating the position of a person or item anywhere at anytime.
2. Description of the Prior Art
Numerous tracking systems have been provided in the prior art. For example, U.S. Pat. Nos. 5,289,163; 5,461,365; 5,461,390; 5,617,074 and 5,627,548 all are illustrative of such prior art While these units may be suitable for the particular purpose to which they address, they would not be as suitable for the purposes of the present invention as heretofore described.
A child position monitoring device monitors the position of a child by detecting the signal strength of a radio frequency carrier from a transmitter attached to the child. If the signal of the radio frequency carrier is too weak, the child is to far away from the adult who has the child position monitoring device. When this happens, the adult is informed that the child has wandered too far away through the use of an audio tone or through the use of vibrations coming from the device. Once the adult is notified that the child is too far away, the device also has a locating display for indicating the relative direction of the child with respect to the adult The display uses eight LEDs arranged around an emblem used to represent the position of the adult. The LED which lights up indicates the relative direction of the child.
A personal alarm system includes a monitoring base station and one or more remote sensing units in two-way radio communication. An electronic handshake between the base station and each remote unit is used to assure system reliability. The remote units transmit at selectable power levels. In the absence of an emergency, a remote unit transmits at a power-conserving low power level. Received field strength is measured to determine whether a remote unit has moved beyond a predetermined distance from the base station. If the distance is exceeded, the remote unit transmits at a higher power level. The remote unit includes sensors for common hazards including water immersion, smoke, excessive heat, excessive carbon monoxide concentration, and electrical shock. The base station periodically polls the remote units and displays the status of the environmental sensors. The system is useful in child monitoring, for use with invalids, and with employees involved in activities which expose them to environmental risk. Alternative embodiments include a panic button on the remote unit for summoning help, and an audible beacon on the remote unit which can be activated from the base station and useful for locating strayed children. In another embodiment, the remote unit includes a Global Positioning System receiver providing location information for display by the base station.
A locator device for monitoring the location of subjects, usable in conjunction with a database system causes a polling signal to be sent periodically to each of the subject's locator devices in the area. The locator device includes a wireless transceiver to receive the polling message and, in response, query a location determination device for the current location of the device. This location is then sent back through the wireless network to the database. The database determines from a record on that particular subject where that subject is supposed to be at that time. If the subject being monitored is not within the area where he or she is supposed to be, then the database may automatically contact law enforcement officials.
A child finder basically consists of a transmitter which is concealingly attachable to a child's body and which sends a signal to a conventional receiver so that the child's location can be continually monitored. The transmitter will typically be carried in an article of jewelry, such as a watch, bracelet, ring, or the like, and will use a special on/off switch which allows the transmitter to be activated only when the jewelry is being worn by the child. The switch includes a reciprocal push button which closes the transmitter's electrical circuit when depressed, and the button is spring-biasedly moved away from electrical contact with the transmitter's circuit when the article of jewelry is not being worn. To protect against inadvertent partial movement of the button which could break electrical contact thus deactivating the transmitter an electrical contact surface of the button is provided with an upwardly extending electrically conductive spring finger which maintains continual electrical contact irrespective of temporary and inadvertent reciprocal movement of the spring finger recedes into a provided groove on the electrical contact surface of the button so as to prevent the finger from causing interference between the primary electrical contact surfaces.
A navigation wrist wear device comprises a GPS receiver fully disposed in a wrist watch type housing. A transparent microwave patch antenna is patterned of indium-tin-oxide on sapphire in front of an LCD time, position and velocity display. A bezel provides a protective window. A low-noise amplifier, down conversion, code processing and navigation processing are all provided on a single integrated circuit Photovoltaic solar cells to each side of the LCD help keep a battery charged.